A micromechanical finite element (FE) framework was developed to predict the viscoelastic properties (complex modulus and creep stiffness) of the asphalt mixtures. The two-dimensional (2D) microstructure of an asphalt mixture was obtained from the scanned image. In the mixture microstructure, irregular aggregates and sand mastic were divided into different subdomains. The FE mesh was generated ...

Ultrasonic elasticity imaging enables visualization of soft tissue deformation for medical diagnosis. Our aim is to understand the role of flow-dependent and flow-independent viscoelastic mechanisms in the response of biphasic polymeric media, including biological tissues and hydrogels, to low-frequency forces. Combining the results of confined and unconfined compression experiments on gelatin ...

There are a number of interesting applications where modeling elastic and/or viscoelastic materials is fundamental, including uses in civil engineering, the food industry, land mine detection and ultrasonic imaging. Here we provide an overview of the subject for both elastic and viscoelastic materials in order to understand the behavior of these materials. We begin with a brief introduction of ...

Simulations of interface evolution and stress distribution near weld line in the viscoelastic melt mold filling process are achieved according to the viscoelastic-Newtonian two-phase model. The finite volume methods on nonstaggered grids are used to solve the model. The level set method is used to capture the melt interface. The interface evolution of the viscoelastic melt in the mold filling p...

Introduction: Mechanical properties of human soft tissues can be investigated in vivo with dynamic magnetic resonance elastography (MRE) by applying low frequency shear waves and measuring the resulting tissue deflections [1]. From these data, elastic and viscoelastic modules are commonly calculated using the algebraic Helmholtz inversion [2,3]. So far, MRE is the only method for a noninvasive ...

Mechanical design of viscoelastic parts fabricated using additive manufacturing technologies are under consideration. Such a design is of great importance for obtaining final products with desired shape and strength which are determined by their stress-strain state. Mathematical model of model of viscoelastic solid which grows due to the process of additive manufacturing is proposed. Complete s...

In this paper, nanostructured carbonated hydroxyapatite powder was synthesized using biomimetic method. Physical properties and morphological features of the powder was studied using appropriate techniques such as BET, TEM, XRD and FTIR. The powder was separately mixed with 3 wt. % solutions of either sodium alginate or chitosan to form different pastes. Rheological behavior of the pastes in os...

A phenomenological approach is used to represent the nonlinear viscoelastic behavior of solid propellants. A three dimensional nite strain viscoelastic model, modi ed by a strain softening function that accounts for damage e ects, is considered in the research. Some of the signi cant aspects of high-elongation propellants are incorporated into the constitutive model. The resulting stress-strain...

In this paper, a dynamic viscoelastic problem is numerically studied. The variational problem is written in terms of the velocity field and it leads to a parabolic linear variational equation. A fully discrete scheme is introduced by using the finite element method to approximate the spatial variable and an Euler scheme to discretize time derivatives. An a priori error estimates result is recal...

In this article, the extensional flow and viscosity and the converging-diverging geometry were examined as the basis of the peculiar viscoelastic behavior in porous media. The modified Bautista-Manero model, which successfully describes shearthinning, elasticity and thixotropic time-dependency, was used for modeling the flow of viscoelastic materials which also show thixotropic attributes. An a...